Illness perceptions and their association with 2 year functional status and change in patients with hand osteoarthritis

Sociodemographic and clinical variables associated with negative illness perception in patients newly diagnosed with rheumatoid arthritis, axial spondyloarthritis, or psoriatic arthritis-a survey based cross-sectional study

When newly diagnosed with inflammatory arthritis (IA), acquiring self-management skills is beneficial, to enhance quality of life. The personal beliefs and mental representations patients hold about their illness, known as illness perception, significantly influence the development of these skills. Recognizing characteristics that affect illness perception is key to identifying patients requiring additional support for the development of self-management skills. This study aimed at identifying the sociodemographic and clinical characteristics associated with a negative illness perception. This cross-sectional study was based on survey data from patients diagnosed for ≤ 2 years. The Brief Illness Perception Questionnaire (B-IPQ) was used to measure illness perception. After psychometric testing, we divided the B-IPQ into two domains: (1) a control domain and (2) a consequence domain. We performed logistic regression analyses with multiple imputations. A total of 1,360 patients (61% females) were included. Among them, 64%, 20%, and 16% were diagnosed with rheumatoid arthritis, psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA), respectively. Younger patients with lower socioeconomic status, a diagnosis of PsA or axSpA, high disease activity (OR 3.026, CI 2.208;4.147), severe physical disability (OR 4.147. CI 2.883;6.007), severe pain (OR 3.034, CI 1.991;4.622), and severe fatigue (OR 2.612, CI 1.942;3.513) were significantly more likely to report having a negative illness perception. Younger patients with a higher symptom burden, increased disease activity, lower socioeconomic status, and a diagnosis of PsA or axSpA may require additional attention and support in rheumatology clinical practice to aid in the development of their self-management skills.

A prospective study of the relationship between illness perception, depression, anxiety, and quality of life in hematopoietic stem cell transplant patients

AIM

The aim of study was to investigate whether depression and anxiety symptoms and illness perception prior to hematopoietic stem cell transplantation (HSCT) predict health related quality of life (HRQOL) at Day 100 and 1 year following HSCT.

METHODS

A total of 205 patients who underwent HSCT (N = 127 autologous transplants, N = 78 allogeneic transplants) were included in this prospective study. Baseline assessment was assessed prior to transplantation and post HSCT data were collected at Day 100 and 1 year. At baseline we assessed depressive symptoms (Patient Health Questionnaire-9), anxiety symptoms (Generalized Anxiety Disorder-7), illness perception (Brief Illness Perception Questionnaire), and HRQOL (Functional Assessment of Cancer Therapy-BMT).

RESULTS

Patients who expressed a greater level of concern about the severity, course, and ability to exert control over one's illness (i.e., illness perception) and who reported a greater level of depression and anxiety symptoms prior to HSCT reported lower HRQOL at both Day 100 and 1 year posttransplant, with a similar degree of association observed at the two follow-up time points.

CONCLUSIONS

Our findings suggest that pretransplant perceptions about their illness and negative mood are significant predictors of HRQOL following HSCT. Illness perception, depression, and anxiety are potentially modifiable risk factors for less than optimal outcome after HCSCT and intervention strategies should be explored.

The Ultrashort Mental Health Screening Tool Is a Valid and Reliable Measure With Added Value to Support Decision-making

BACKGROUND

Mental health influences symptoms, outcomes, and decision-making in musculoskeletal healthcare. Implementing measures of mental health in clinical practice can be challenging. An ultrashort screening tool for mental health with a low burden is currently unavailable but could be used as a conversation starter, expectation management tool, or decision support tool.

QUESTIONS/PURPOSES

(1) Which items of the Pain Catastrophizing Scale (PCS), Patient Health Questionnaire (PHQ-4), and Brief Illness Perception Questionnaire (B-IPQ) are the most discriminative and yield a high correlation with the total scores of these questionnaires? (2) What is the construct validity and added clinical value (explained variance for pain and hand function) of an ultrashort four-item mental health screening tool? (3) What is the test-retest reliability of the screening tool? (4) What is the response time for the ultrashort screening tool?

METHODS

This was a prospective cohort study. Data collection was part of usual care at Xpert Clinics, the Netherlands, but prospective measurements were added to this study. Between September 2017 and January 2022, we included 19,156 patients with hand and wrist conditions. We subdivided these into four samples: a test set to select the screener items (n = 18,034), a validation set to determine whether the selected items were solid (n = 1017), a sample to determine the added clinical value (explained variance for pain and hand function, n = 13,061), and a sample to assess the test-retest reliability (n = 105). Patients were eligible for either sample if they completed all relevant measurements of interest for that particular sample. To create an ultrashort screening tool that is valid, reliable, and has added value, we began by picking the most discriminatory items (that is, the items that were most influential for determining the total score) from the PCS, PHQ-4, and B-IPQ using chi-square automated interaction detection (a machine-learning algorithm). To assess construct validity (how well our screening tool assesses the constructs of interest), we correlated these items with the associated sum score of the full questionnaire in the test and validation sets. We compared the explained variance of linear models for pain and function using the screening tool items or the original sum scores of the PCS, PHQ-4, and B-IPQ to further assess the screening tool's construct validity and added value. We evaluated test-retest reliability by calculating weighted kappas, ICCs, and the standard error of measurement.

RESULTS

We identified four items and used these in the screening tool. The screening tool items were highly correlated with the PCS (Pearson coefficient = 0.82; p < 0.001), PHQ-4 (0.87; p < 0.001), and B-IPQ (0.85; p < 0.001) sum scores, indicating high construct validity. The full questionnaires explained only slightly more variance in pain and function (10% to 22%) than the screening tool did (9% to 17%), again indicating high construct validity and much added clinical value of the screening tool. Test-retest reliability was high for the PCS (ICC 0.75, weighted kappa 0.75) and B-IPQ (ICC 0.70 to 0.75, standard error of measurement 1.3 to 1.4) items and moderate for the PHQ-4 item (ICC 0.54, weighted kappa 0.54). The median response time was 43 seconds, against more than 4 minutes for the full questionnaires.

CONCLUSION

Our ultrashort, valid, and reliable screening tool for pain catastrophizing, psychologic distress, and illness perception can be used before clinician consultation and may serve as a conversation starter, an expectation management tool, or a decision support tool. The clinical utility of the screening tool is that it can indicate that further testing is warranted, guide a clinician when considering a consultation with a mental health specialist, or support a clinician in choosing between more invasive and less invasive treatments. Future studies could investigate how the tool can be used optimally and whether using the screening tool affects daily clinic decisions.

LEVEL OF EVIDENCE

Level II, diagnostic study.

Prognostic value of illness perception on changes in knee pain among elderly individuals: Two-year results from the Frederiksberg Cohort study

Objective

To investigate the prognostic value of illness perception (IP) on knee pain, quality of life (QoL) and functional level in elderly individuals reporting knee pain.

Design

A prospective cohort study of 1552 elderly with knee pain comparing two previously established clusters based on the Brief Illness Perception questionnaire. Cluster 1 ("Concerned optimists" [hypothesized unfavorable profile]; n ​= ​642) perceived their knee pain as a greater threat to them than Cluster 2 ("Unconcerned confident" [hypothesized favorable profile]; n ​= ​910). Primary outcome was the change from baseline to year 2 in the KOOS Pain subscale. Secondary outcomes were changes from baseline in quality of life (EuroQol-5 Domain and EQ VAS) and in the KOOS subscales Symptom, Activities of Daily Living, Knee-related QoL and Sports and recreation. Analyses were done on the original Intention-To-Survey (ITS) population, using repeated measures mixed linear models.

Results

Among the ITS population, 841 (54%) responded to the 2-year survey. There was a statistically significant but clinically irrelevant cluster difference in the 2-year change from baseline in KOOS pain (mean difference: 6.0 KOOS points [95% CI: 7.3 to -4.7]) explained by a minor improvement in Cluster 1: (6.2 points) and no changes in Cluster 2: (0.2 points). Comparable results were found across the secondary outcomes. Clinically irrelevant cluster changes in IP were seen.

Conclusion

In a cohort of people with knee pain, IP phenotype (i.e., Clusters) were of no prognostic value for the 2-year changes in pain, function, and QoL. Targeting IP may not be relevant in this patient population.

Trial registration number and date of registration

The Frederiksberg Cohort study was pre-registered at clinicaltrials.gov (NCT03472300) on March 21, 2018.

Determination and characterization of patient subgroups based on pain trajectories in hand osteoarthritis

OBJECTIVES

To investigate pain, pain trajectories and their determinants in hand osteoarthritis (OA).

METHODS

Data from the HOSTAS (Hand OSTeoArthritis in Secondary care) consisting of consecutive hand OA patients were used. Australian Canadian Osteoarthritis Hand Index (AUSCAN) pain was measured yearly for four years. Patients with complete AUSCAN at ≥2 time points were eligible for longitudinal analysis. Associations between variables of interest and baseline AUSCAN pain were investigated with linear regression. Development of pain over time was modelled using latent class growth analysis (LCGA). Associations of LCGA classes with variables of interest were analysed using multinomial logistic regression adjusted for baseline pain.

RESULTS

A total of 484/538 patients [mean (s.d.) age 60.8 (8.5) years, 86% women, mean (s.d.) AUSCAN pain 9.3 (4.3)] were eligible for longitudinal analysis. Sex, marital and working status, education, disease duration and severity, anxiety and depression scores, lower health-related quality of life (HR-QoL), specific illness perceptions and coping styles were associated with baseline pain. LCGA yielded three classes, characterized by average pain levels at baseline; average pain remained stable over time within classes. Classes with more pain were positively associated with BMI, tender joint count, symptom duration, hand function scores and depression scores, negatively with physical HR-QoL, and education level.

CONCLUSION

Baseline pain was associated with patient and disease characteristics, and psychosocial factors. LCGA showed three pain trajectories in hand OA patients, with different baseline pain levels and stable pain over time. Classes were distinguished by BMI, education level, disease severity, depression and HR-QoL.

Longitudinal trajectories of illness perception regarding breast cancer-related lymphedema among women with breast cancer

OBJECTIVE

To identify longitudinal trajectories of illness perception (IP) regarding breast cancer-related lymphedema (BCRL) in the first six months after surgery among women with breast cancer and to explore the predictive effects of demographics and clinical factors on IP trajectories.

METHODS

From August 2019 to August 2021, a total of 352 patients participated in this study, 328 of whom were included in the data analysis. Demographic and clinical characteristics were collected at baseline (1-3 days after surgery). The BCRL-specific revised illness perception questionnaire was used to measure IP regarding BCRL at baseline and 1 month, 3 months and 6 months post-surgery. A multilevel model was conducted to analyze the data.

RESULTS

Over the first six months post-surgery, the "timeline acute/chronic" and "illness coherence" dimensions showed positive growth trajectories; the "personal control" and "treatment control" dimensions presented negative growth trajectories; and the trajectories of identity, consequences, cyclicality and emotional influence perceptions regarding BCRL showed no significant changes. Age, education level, marital status, employment status, family monthly income per person, cancer stage and status of removed lymph nodes were indicated to be predictive factors of IP trajectories.

CONCLUSIONS

The present study determined significant changes over the first six months post-surgery in four IP dimensions and predictive effects of some demographics and clinical details on IP trajectories. These findings may help healthcare providers know more about the dynamic characteristics of IPs regarding BCRL in patients with breast cancer and assist them in identifying patients with a tendency toward improper IP regarding BCRL.

Illness perceptions and health-related quality of life in individuals with overweight and obesity

INTRODUCTION

To understand how individuals (self-)manage obesity, insight is needed into how patients perceive their condition and how this perception translates into health outcomes (e.g., health-related quality of life, HRQOL). Our objectives were (1) to examine illness perceptions in individuals with overweight and obesity, and (2) to investigate associations of these perceptions with physical and mental HRQOL.

METHODS

In a cross-sectional analysis of the Netherlands Epidemiology of Obesity Study (n = 6432; 52% women), illness perceptions were assessed using the Brief Illness Perception Questionnaire, and HRQOL was assessed using the 36-Item Short-Form Health Survey. Illness perceptions were calculated for different categories of overall, abdominal, and metabolically unhealthy obesity. We investigated associations of illness perceptions with HRQOL using BMI-stratified multivariable linear regression analyses.

RESULTS

Compared to individuals with normal weight, individuals with obesity believed to a higher extent that their condition had more serious consequences [Mean Difference (95%CI): 1.8 (1.6-2.0)], persisted for a longer time [3.4 (3.2-3.6)], manifested in more symptoms [3.8 (3.6-4.0)], caused more worry [4.2 (3.9-4.4)] and emotional distress [2.0 (1.8-2.2)], but was more manageable with medical treatment [3.1 (2.9-3.4)]. They perceived to a lesser extent that they had personal control [-2.2 (-2.4, -2.0)] and understanding [-0.3 (-0.5, -0.1)] regarding their condition. These negative perceptions were less pronounced in individuals with abdominal obesity. Behaviour/Lifestyle was attributed by 73% of participants to be the cause of their obesity. Stronger negative illness perceptions were associated with impaired HRQOL, particularly the physical component.

CONCLUSION

Individuals with obesity perceived their conditions as threatening, and this seemed somewhat stronger in individuals with overall obesity than those with abdominal obesity. Behaviour/Lifestyle is a crucial target intervention and empowering self-management behaviour to achieve a healthy body weight may deliver promising results. In addition, strategies that aim to change negative perceptions of obesity into more adaptive ones may improve HRQOL.

Do Illness Perceptions and Coping Strategies Change Over Time in Patients Recently Diagnosed With Axial Spondyloarthritis?

OBJECTIVE

It is unknown if in axial spondyloarthritis (axSpA) patients' illness perceptions and coping strategies change when disease activity changes.

METHODS

Patients diagnosed with axSpA and with 1 or more follow-up visits (1 and/or 2 yrs in the SPACE cohort) were included. Mixed linear models were used for illness perceptions (range 1-5), coping (range 1-4), back pain (numeric rating scale range 0-10), health-related quality of life (range 0-100), physical and mental component summary (PCS and MCS; range 0-100), work productivity loss (WPL; range 0-100), and activity impairment (AI; range 0-100%), separately, to test if they changed over time.

RESULTS

At baseline, 150 axSpA patients (mean age 30.4 yrs, 51% female, 65% HLA-B27+) had a mean (SD) numeric rating scale back pain of 4.0 (2.5), PCS of 28.8 (14.0), MCS of 47.8 (12.4), WPL of 34.1% (29.8), and AI of 38.7% (27.9). Over 2 years, clinically and statistically significant improvements were seen in the proportion of patients with an Ankylosing Spondylitis Disease Activity Score (ASDAS) of low disease activity (from 39% at baseline to 68% at 2 years), back pain (-1.5, SD 2.2), AI (-14.4%, SD 27.2), PCS (11.1, SD 13.3), and WPL (-15.3%, SD 28.7), but MCS did not change (0.7, SD 13.9; P = 0.201). In contrast, illness perceptions and coping strategies did not change over a period of 2 years. For example, at 2 years patients believed that their illness had severe "consequences" (2.8, SD 0.9) and they had negative emotions (e.g., feeling upset or fear) towards their illness ["emotional representation", 2.5 (0.8)]. Patients most often coped with their pain by putting pain into perspective ["comforting cognitions", 2.8 (0.6)] and tended to cope with limitations by being optimistic ["optimism", 2.9 (0.7)].

CONCLUSION

While back pain, disease activity, and health outcomes clearly improved over 2 years, illness perceptions and coping strategies remained remarkably stable.

Cross-cultural translation, adaptation and validation of a Japanese version of the functional index for hand osteoarthritis (J-FIHOA)

Background

Hand osteoarthritis (OA) has a wide spectrum of clinical presentations and physical function is one of the core domains where patients suffer. The Functional Index for Hand Osteoarthritis (FIHOA) is a leading assessment tool for hand OA-related functional impairment. Our objective was to make a Japanese version of FIHOA (J-FIHOA) and validate it among Japanese hand OA patients.

Methods

Forward and backward translation processes were completed to create a culturally adapted J-FIHOA. A prospective, observational multicenter study was undertaken for the validation process. Seventeen collaborating hospitals recruited Japanese hand OA patients who met the American College of Rheumatology criteria. A medical record review and responses to the following patient-rated questionnaires were collected: J-FIHOA, Hand20, Health Assessment Questionnaire (HAQ), numerical rating scale for pain (NRS pain) and Short Form 36 Health Survey (SF-36). We explored the structure of J-FIHOA using factor analysis. Cronbach’s alpha coefficients and item-total correlations were calculated. Correlations between J-FIHOA and other questionnaires were evaluated for construct validity. Participants in clinically stable conditions repeated J-FIHOA at a one- to two-week interval to assess test-retest reliability. To evaluate responsiveness, symptomatic patients who started new pharmacological treatments had a 1-month follow-up visit and completed the questionnaires twice. Effect size (ES) and standardized response mean (SRM) were calculated with pre- and post-treatment data sets. We assessed responsiveness, comparing ES and SRM of J-FIHOA with other questionnaires (construct approach).

Results

A total of 210 patients participated. J-FIHOA had unidimensional structure. Cronbach’s alphas (0.914 among females and 0.929 among males) and item-total correlations (range, 0.508 to 0.881) revealed high internal consistency. Hand20, which measures upper extremity disability, was strongly correlated with J-FIHOA (r = 0.82) while the mental and role-social components of SF-36 showed no correlations (r = − 0.24 and − 0.26, respectively). Intraclass correlation coefficient for test-retest reliability was 0.83 and satisfactory. J-FIHOA showed the highest ES and SRM (− 0.68 and − 0.62, respectively) among all questionnaires, except for NRS pain.

Conclusions

Our results showed J-FIHOA had good measurement properties to assess physical function in Japanese hand OA patients both for ambulatory follow-up in clinical practice, and clinical research and therapeutic trials.

Patients With Thumb-base Osteoarthritis Scheduled for Surgery Have More Symptoms, Worse Psychological Profile, and Higher Expectations Than Nonsurgical Counterparts: A Large Cohort Analysis

BACKGROUND

Psychological characteristics, such as depression, anxiety or negative illness perception are highly prevalent in patients with several types of OA. It is unclear whether there are differences in the clinical and psychological characteristics of patients with thumb carpometacarpal (CMC-1) osteoarthritis (OA) scheduled for nonsurgical treatment and those with surgical treatment.

QUESTIONS/PURPOSES

(1) What are the differences in baseline sociodemographic characteristics and clinical characteristics (including pain, hand function, and health-related quality of life) between patients with thumb CMC-1 OA scheduled for surgery and those treated nonoperatively? (2) What are the differences in psychological characteristics between patients scheduled for surgery and those treated nonsurgically, for treatment credibility, expectations, illness perception, pain catastrophizing, and anxiety and depression? (3) What is the relative contribution of baseline sociodemographic, clinical, and psychological characteristics to the probability of being scheduled for surgery?

METHODS

This was a cross-sectional study using observational data. Patients with CMC-1 OA completed outcome measures before undergoing either nonsurgical or surgical treatment. Between September 2017 and June 2018, 1273 patients were screened for eligibility. In total, 584 participants were included: 208 in the surgery group and 376 in the nonsurgery group. Baseline sociodemographic, clinical, and psychological characteristics were compared between groups, and a hierarchical logistic regression analysis was used to investigate the relative contribution of psychological characteristics to being scheduled for surgery, over and above clinical and sociodemographic variables. Baseline measures included pain, hand function, satisfaction with the patient's hand, health-related quality of life, treatment credibility and expectations, illness perception, pain catastrophizing, and anxiety and depression.

RESULTS

Patients in the surgery group had longer symptom duration, more often a second opinion, higher pain, treatment credibility and expectations and worse hand function, satisfaction, HRQoL, illness perception and pain catastrophizing compared with the non-surgery group (effect sizes ranged from 0.20 to 1.20; p values ranged from < 0.001 to 0.044). After adjusting for sociodemographic, clinical, and psychological factors, we found that the following increased the probability of being scheduled for surgery: longer symptom duration (standardized odds ratio [SOR], 1.86; p = 0.004), second-opinion visit (SOR, 3.81; p = 0.027), lower satisfaction with the hand (SOR, 0.65; p = 0.004), higher treatment expectations (SOR, 5.04; p < 0.001), shorter perceived timeline (SOR, 0.70; p = 0.011), worse personal control (SOR, 0.57; p < 0.001) and emotional response (SOR, 1.40; p = 0.040). The hierarchical logistic regression analysis including sociodemographic, clinical, and psychological factors provided the highest area under the curve (sociodemographics alone: 0.663 [95% confidence interval 0.618 to 0.709]; sociodemographics and clinical: 0.750 [95% CI 0.708 to 0.791]; sociodemographics, clinical and psychological: 0.900 [95% CI 0.875 to 0.925]).

CONCLUSIONS

Patients scheduled to undergo surgery for CMC-1 OA have a worse psychological profile than those scheduled for nonsurgical treatment. Our findings suggest that psychological characteristics should be considered during shared decision-making, and they might indicate if psychological interventions, training in coping strategies, and patient education are needed. Future studies should prospectively investigate the influence of psychological characteristics on the outcomes of patients with CMC-1 OA.

LEVEL OF EVIDENCE

Level III, therapeutic study.

Which Psychological Variables Are Associated With Pain and Function Before Surgery for de Quervain's Tenosynovitis? A Cross-sectional Study

BACKGROUND

Depression, anxiety, and pain catastrophizing have been associated with worse pain and function in studies of patients with de Quervain's tenosynovitis. Illness perceptions are the patient's thoughts and feelings about their illness. More negative perceptions of the illness such as the illness having a long duration or serious consequences are associated with worse physical function in patients with hand osteoarthritis. It is currently unknown whether these psychological factors play a similar role in de Quervain's. We chose to study patients who have tried nonoperative management and have chosen surgical decompression due to persistent symptoms. Psychological factors may be associated with their ongoing pain and impaired function, so it is particularly important to investigate the role of psychosocial factors that may be targeted with non-invasive interventions.

QUESTIONS/PURPOSES

Which psychological variables are independently associated with baseline pain and function in patients undergoing surgical treatment for de Quervain's tenosynovitis, after controlling for clinical and demographic variables?

METHODS

This cross-sectional study included data from a longitudinally maintained database on 229 patients who had surgery for de Quervain's tenosynovitis between September 2017 and October 2018. All management options were discussed with patients, but many had already tried nonoperative management and chose surgery once referred to our institution. Our database included 958 patients with de Quervain's, with 69% (659) managed nonoperatively and 34% (326 of 958) who underwent surgical decompression. A total of 70% (229 of 958) completed all questionnaires and could be included in the study. With the numbers available, we found no differences between those included and those not analyzed in terms of age, gender, duration of symptoms, BMI, smoking status, and workload.Patients completed the Patient-Rated Wrist/Hand Evaluation (PRWHE), Patient Health Questionnaire for emotional distress, Pain Catastrophizing Scale (PCS), and the Brief Illness Perception Questionnaire. We investigated the relative contribution of patient demographics and individual psychosocial factors using a hierarchical multivariable linear regression model. In the first step we considered how demographic factors were associated with the baseline PRWHE score. In the second step we investigated the effect of pain catastrophizing and emotional distress on the baseline PRWHE score after accounting for confounding demographic factors. In the final step, the effect of illness perceptions on baseline PRWHE were considered after accounting for the confounding effects of demographic factors as well as pain catastrophizing and emotional distress.

RESULTS

After controlling for confounding variables including workload and emotional distress, a more negative patient perception of the consequences of their condition and worse pain catastrophizing were associated with worse pain and function (consequences, β = 0.31; p < 0.01, pain catastrophizing β = 0.17; p = 0.03). A hierarchical multivariable regression analysis found that 11% of variance in baseline pain and function was explained by pain catastrophizing and emotional distress. Illness perceptions brought the total explained variance of the final model to 34%.

CONCLUSIONS

More negative perceptions of the consequences of de Quervain's tenosynovitis and worse pain catastrophizing are associated with worse pain and reduced function at baseline in patients awaiting surgical decompression of de Quervain's tenosynovitis. In light of these findings, future studies might explore interventions to reduce pain catastrophizing and lower the perceived consequences of the condition. This may reduce the number of patients choosing surgical decompression or may also improve surgical outcomes. Further work should consider if these psychological factors are also associated with postoperative patient-reported outcomes.

LEVEL OF EVIDENCE LEVEL

III, therapeutic study.

Influence of illness perceptions, psychological distress and pain catastrophizing on self-reported symptom severity and functional status in patients with carpal tunnel syndrome

OBJECTIVE

To examine the influence of illness perceptions, pain catastrophizing and psychological distress on self-reported symptom severity and functional status in patients diagnosed with carpal tunnel syndrome (CTS).

METHODS

A total of 674 patients with CTS scheduled for surgery at an outpatient treatment center for hand and wrist conditions (September 2017 to August 2018) completed online questionnaires regarding demographic and psychosocial characteristics and self-reported CTS severity. Self-reported severity of CTS was measured with the functional status scale and the symptom severity scale of the Boston Carpal Tunnel Questionnaire. To measure psychosocial factors, the Patient Health Questionnaire-4, Pain Catastrophizing Scale and the Brief Illness Perception Questionnaire were used. Pearson correlation coefficients were calculated to assess univariable relations. Hierarchical linear regression models were used to examine the relation between psychosocial factors and self-reported severity, and the relative contribution of psychosocial factors to self-reported severity, adjusting for patient characteristics and comorbidities.

RESULTS

Medium-sized correlations (range 0.32-0.44) with self-reported severity were observed for psychological distress, pain catastrophizing, consequences, identity, concern and emotional representation. Furthermore, these factors (except for concern) were also associated with self-reported severity, when adjusted for baseline characteristics and comorbidities. Hierarchical linear regression models showed that these psychosocial factors explained an additional 20-25% of the variance in self-reported severity of CTS.

CONCLUSION

This study shows that psychological distress, pain catastrophizing and illness perceptions play an independent role in self-reported severity of CTS. Clinicians should take these psychosocial factors into account when they are consulted by patients with CTS.

Prevalence of self-reported knee symptoms and management strategies among elderly individuals from Frederiksberg municipality: protocol for a prospective and pragmatic Danish cohort study

INTRODUCTION

The Global Burden of Disease 2010 study ranked osteoarthritis (OA) as a leading cause of years lived with disability. With an ageing population, increasing body weight and sedentary lifestyle, a substantial increase especially in knee OA (KOA) is expected. Management strategies for KOA include non-pharmacological, pharmacological and surgical interventions. Meanwhile, over-the-counter pain medications have been discredited as they are associated with several risks with long-term usage. By consequence, the use of exercise and all sorts of complementary and alternative medicine (CAM) for joint pain has increased. The available self-management strategies are plenty, but there is no overview of their use at a population level and whether they are used along with doctors' prescriptions or replace these. The aim of this study is to estimate the population incidence of developing knee symptoms and analyse the association between (and impact of) the use of self-reported preventive measures and knee symptoms.

METHODS AND ANALYSIS

This prospective cohort study pragmatically recruits individuals from the municipality of Frederiksberg, Denmark. All citizens aged 60-69 years old will be contacted annually for 10 years and asked to participate in a web-based survey. The major outcomes are self-reported knee symptoms and their association with use of various management strategies, including use of non-pharmacological treatments and CAM. Secondary outcomes include the influence of treatments on use of healthcare system and surgical procedures. Descriptive and analytic statistics (eg, logistic regression) will be used to provide summaries about the sample and observations made and the associations between self-management and development of knee symptoms.

ETHICS AND DISSEMINATION

This study can be implemented without permission from the Health Research Ethics Committee. Permission has been obtained from the Danish Data Protection Agency. Study findings will be disseminated in peer-reviewed journals and presented at relevant conferences.

TRIAL REGISTRATION NUMBER

NCT03472300.